mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-04 09:09:56 +00:00
aa9bc17601
BMakefiles and other bits will follow. Requested by: Andrey Chernov Made world by: Chuck Robey
76 lines
1.9 KiB
C
76 lines
1.9 KiB
C
/* mpf_sqrt -- Compute the square root of a float.
|
|
|
|
Copyright (C) 1993, 1994, 1996 Free Software Foundation, Inc.
|
|
|
|
This file is part of the GNU MP Library.
|
|
|
|
The GNU MP Library is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU Library General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or (at your
|
|
option) any later version.
|
|
|
|
The GNU MP Library is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
|
|
License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public License
|
|
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
|
|
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
|
|
MA 02111-1307, USA. */
|
|
|
|
#include "gmp.h"
|
|
#include "gmp-impl.h"
|
|
|
|
void
|
|
#if __STDC__
|
|
mpf_sqrt (mpf_ptr r, mpf_srcptr u)
|
|
#else
|
|
mpf_sqrt (r, u)
|
|
mpf_ptr r;
|
|
mpf_srcptr u;
|
|
#endif
|
|
{
|
|
mp_size_t usize;
|
|
mp_ptr up, tp;
|
|
mp_size_t prec;
|
|
mp_exp_t tsize, rexp;
|
|
TMP_DECL (marker);
|
|
|
|
usize = u->_mp_size;
|
|
if (usize <= 0)
|
|
{
|
|
usize = 1 - 1 / (usize == 0); /* Divide by zero for negative OP. */
|
|
r->_mp_size = usize; /* cheat flow by using usize here */
|
|
r->_mp_exp = 0;
|
|
return;
|
|
}
|
|
|
|
TMP_MARK (marker);
|
|
|
|
prec = r->_mp_prec;
|
|
rexp = (u->_mp_exp + 1) >> 1; /* round towards -inf */
|
|
tsize = 2 * prec + (u->_mp_exp & 1);
|
|
|
|
up = u->_mp_d;
|
|
tp = (mp_ptr) TMP_ALLOC (tsize * BYTES_PER_MP_LIMB);
|
|
|
|
if (usize > tsize)
|
|
{
|
|
up += usize - tsize;
|
|
usize = tsize;
|
|
MPN_COPY (tp, up, tsize);
|
|
}
|
|
else
|
|
{
|
|
MPN_ZERO (tp, tsize - usize);
|
|
MPN_COPY (tp + (tsize - usize), up, usize);
|
|
}
|
|
|
|
mpn_sqrtrem (r->_mp_d, NULL, tp, tsize);
|
|
|
|
r->_mp_size = (tsize + 1) / 2;
|
|
r->_mp_exp = rexp;
|
|
TMP_FREE (marker);
|
|
}
|